It's tough. I can't control it either. Maybe just stop doing things that cause anger and anxiety. I never play multiplayer games because of that. Why bother with something that you don't have total control with?
A good sleep and exercising actually don't help, at least they don't for me.
Find something else to do for fun. You want fun, not anxiety.
Oh, and don't get kids too early. You can't control kids so they are a big source of anxiety.
BTW venting online (like what you are doing now) actually helps a bit, at least for me. You can even insult a bit here and remove the post later before someone notices.